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Finding the Fourth Proportional to 201.40, 278.13 and 139.39

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Solution

The fourth proportional to 201.40, 278.13 and 139.39 is: 192.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    201.40 : 278.13 = 139.39 : x
  2. Step 2: Convert to fraction form
    201.40/278.13 = 139.39/x
  3. Step 3: Cross multiply
    201.40x = 278.13 × 139.39
  4. Step 4: Simplify right side
    201.40x = 38,768.54
  5. Step 5: Solve for x
    x = 38,768.54/201.40
  6. Step 6: Final answer
    x = 192.50

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.